How to downgrade Nokia e51 firmware

Can anybody tell me how it is possible to downgrade the firmware of a nokia e51 ( due to wi-fi problems woth 400.34.011 ). I have used Navifirm to download the firmware files. I also have Nokia care suite, phoenix, and JAF. Jaf gives me this error. "Error reading phone init data...". Phoenix tells me that the phone won't allow downgrade, even though i selected downgrade in options.

Can i please get some help here?

ps is there another third party flasher i can resort to?